The routing over different domains on the Internet is performed through the protocol known as Border Gateway Protocol (BGP). For a general discussion of the characteristics and modes of use of the BGP protocol reference may be made to the document “A Border Gateway Protocol 4 (BGP-4)” by Y. Rekhter and T. Li, RFC 1771, T. J. Watson Research Center, Cisco, March 1995.
The BGP protocol allows each autonomous system (AS) to adopt its own policy in selecting the paths and propagating the reachability information on the other network users. These routing policies may however be dependent upon contractual commercial agreements among different administrative domains. For instance, an autonomous system AS may choose the policy of not providing transit services among its providers.
An evaluation of a provider connectivity, solely referred to the “technical” capability of a provider of transmitting information over the network, may be obtained by making resort to various solutions, commonly known in the present is art. However, such a solution is not capable of characterizing in a complete and fully correct way the features of a network such as the Internet.
Solutions have already been worked out which allow it in some way to infer the existence of specific customer/provider relationships on the network.
A solution of this kind is described for instance in the document “On inferring autonomous system relationships in the Internet” by Lixin Gao, GLOBECOM 2000-IEEE Global Telecommunications Conference, no. 1, November 2000, pages 387-396.
The solutions according to the present art considered above have in any case the drawback of providing in the whole a partial overview of the connectivity characteristics of the network, in particular concerning the overwhelming weight given to the physical transport characteristics of the network itself.